Rail joint



March 22, 1960 SABLOTNIE 2,929,560

RAIL JOINT Filed May 23, 1955 Fly. F .2

RAIL 39M Heinrich Sahlotnie, Dortmnnd-Kirchhorde, Germany Application May 23, 1955, Serim No. 516,359

In Germany October 8, 1949 Public Law 619, August 23, 1954 Patent expires Gctober 8, 1969 4 Claims. (Cl. 238-204) The invention is relating to a rail joint arrangement for electric driven railways particularly for hauling tracks in mines. For these electric tracks, the first requirement is a faultless metallic connection between the ends of rails serving as return line. It was tried to meet this requirement by connecting the rail ends by two fish-plates and bolts and welding them on a bed-plate and, if necessary, also welding the rail ends to each other. This type of joint has the disadvantage that the welds are not resistant to heavy stresses due to which they may break, and that besides of that the rail heads which are annealed by the welding heat become soft and uneveness is resultant on such spots subject to higher wear. The performance of welding operations in a mine increases the explosion hazards considerably.

According to the invention described a type of rail joint has been developed by which all these disadvantages are overcome. It consists of a shoe of about 30 cm. length with an appropriate recess on the rail base and the rail web so that the rail ends can be pushed in from the two front faces until they are in contact in the centre. To ensure a safe seat of the rail ends in the shoe, there is provided at the point of transition from the rail base to rail web on both sides a further recess for keys. The arrangement is such that the keys employed at both sides of the rail web with its guides are directed opposite to each other so that one key can be driven in from the rear face and the other one from the front face. It is obvious that owing to the length of the keys which is equal to that of the shoes incidental loosening is practically impossible. In order to secure further particularly the current conduction, the keys may be provided on their faces in contact with the rail with a longitudinal groove for the location of a cable with good electric conductive properties, for instance a copper cable. This cable can on its ends be bent over and the ends be installed in the adequate bore holes provided on the two ends of the groove. When driving in the keys, the cables are subject to a certain deformation by being closely pressed against the rail web. The keys and their guides can on their vertical oblong face also be tapered.

The shoes can be installed at certain distances, for instance, with 50 meters spacings.

The drawing shows an example for the design of a new joint arrangement, for instance Figure 1 is a sectional view of a rail before the joint,

Figure 2 is a sectional view of the rail with transverse web before the joint,

Figure 3 is a longitudinal sectional view taken on line 3-3 of Fig. 1,

Figure 4 is a side elevational view of the key,

7 Figure 5 is a sectional view taken on line 5-5 of Fig. 4,

Figure 6 is a side elevational view of the modified joint of Fig. 3.

"I nited States Patent 0 Figure 7 is a sectional view taken on line 77 of Fig. 5,

A shoe a is made of a material with good properties regarding strength and electricity conduction and shows a main passage to suit the base and web of rail ,b, including recesses c and c' which are tapered oppositely on opposite sides of the rail web and are suitable to receive adequately shaped keys d driven in from opposite directions. These keys show a groove e on the side in contact with the rail web and are provided at the ends of the groove e with boreholes f, in which a cable (Fig. 7) of good electric conductive material is installed; this cable is, when driving in the keys in close contact with the web of the rail joints for good conducting of electric current. The type of joint shown in Figures 2 and 6 is on its under surface equipped with a transverse web g that has a passage h that extends in a direction perpendicular to the longitudinal axis for a connection or bus bar 1', which serves as a modified joint showing the electric connection from one rail track to the other. The passage 11 includes a tapered guideway or slot k, which receives a key 1'. For economic reason with regard to material savings, the external section of the joint can have a contour as shown in the views in broken lines and with only a few ribs shaped in accordance with the showing in full lines (Fig. l). The main passage includes a slot for the webs of the abutting rail end portions, and the shoe a is provided with two opposite top surfaces that abut from below against the lower surfaces of the rail heads.

I claim:

1. A rail joint for electric railway tracks, comprising in combination, an elongated shoe having an internal passage extending throughout the length of said shoe and open at both opposite ends, said passage having a lower section formed to receive the rail base and the rail web of each of two abutting rail end portions having rail heads at the tops of said webs, and said shoe having two wedgeshaped recesses respectively extending from opposite ends of the shoe longitudinally thereof beyond the abutting rail end portions and forming part of said passage, each recess being disposed on an opposite side of said rail webs, the taper of the wedge of each recess being opposite to that of the other, and each recess being adapted to receive a key driven in from a direction oppositely relative to that of the other recess, and a wedge-shaped key disposed in each recess in wedged engagement between said shoe and rail end portions.

2. In a rail joint as claimed in claim 1, each key having a face abutting against the rail web surfaces on one rail side, said face having an elongated groove extending across the abutting rail end portions.

3. In a rail joint as claimed in claim 1, each key having a face designed to abut against the rail web surfaces on one rail side, said face defining an elongated groove extending across the abutting rail end portions, said key having two bores transverse of its longitudinal extension and disposed at the ends of, and intercommunicating with said groove.

4. In a rail joint as claimed in claim 1, said shoe having a central longitudinal slot forming an upward extension of said passage through which the rail webs extend, said shoe having two opposite top surfaces at opposite sides of said slot engaging the lower surfaces of the rail heads, respectively.

References Cited in the file of this patent UNITED STATES PATENTS 

